


Mucus Madness

by ForbiddenArchive



Series: January Batch 2021 [5]
Category: Monster Girl Encyclopedia
Genre: Corruption, F/M, Incest, Transformation
Language: English
Status: Completed
Published: 2021-03-03
Updated: 2021-03-03
Packaged: 2021-03-16 03:41:42
Rating: Explicit
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 1
Words: 1,613
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29818890
Author URL: https://archiveofourown.org/users/ForbiddenArchive/pseuds/ForbiddenArchive
Summary: A youth goes looking for his sister, not knowing that she's already fallen prey to the monsters lurking around their home.
Series: January Batch 2021 [5]
Series URL: https://archiveofourown.org/series/2190444
Kudos: 12





	Mucus Madness

**Author's Note:**

> For Anonymous.

“Anko! Anko-oneechan!”

The voice that flew through the air belonged to a young boy. A boy by the name of Tohru. A boy that had been walking through dirt and grime for the last hour or so, desperately looking for his older sister. It had been a day since she had left their home, and since neither of them had any parents left after the incident that drove them from their village… He had to go look for her himself.

Of course, he was worried. Worried that she could’ve been hurt. Worried that she could’ve been turned into a Monster. After all, that was what had happened to their old home. One of the elders had taken in a young Monster, and one thing led to another before it all devolved into pure degeneracy…

“Please be okay, Anko-oneechan...!” Tohru muttered to himself as he dashed through the grass around him, the rain pouring down as he made his way into the nearby wetlands. His sister had to go through this place if she wanted to get them some food, and the native Monsters were especially dangerous considering the difficult terrain.

The youth rubbed his forehead, wiping it free from any sweat that had built up, as he tried to look around for any sign of his sister. Anything. Even a Monster that looked out of place would help. He just needed something!

“Anko-oneechan! ANKO-ONEECHAN!” He shouted once more, trying to get her attention. And if that failed, he didn’t care that he’d end up in danger. He wanted his sister to be safe more than anything. He didn’t care that he was risking his own…

Just then, he heard a sharp breath and a bit of coughing, as well as gurgling coming from up ahead. Sickly sounds. It almost sounded like one of the older women that he had personally seen transform into a Monster, before she tried to turn on him…

“Anko-oneechan!” Tohru cried out as he ran towards the source of the sounds. It had to be her. Nobody else would be in danger around here, not after everything that had happened..!

Sure enough, and luckily for the boy, he found the brunette collapsed up against one of the trees, partly sinking into the mud below. His beloved sister, Anko.

“T-Tohru… W-Why did you…” Anko muttered, barely able to see straight. It was easy to tell that she had been attacked, given the mucus-like liquids that were covering her. Her head, her torso, everything was slathered in that disgusting slime-like stuff, and her body had been stripped, leaving some of the mud to get on her just the same…

Her dear brother, the cute little brunette that he was, dashed towards her with a bright smile. “Anko-oneechan, I was so worried..!” He cried out, quickly wrapping his arms around her sticky body. His relief at seeing her in one piece was everything he needed. Because she was safe…

“Tohru…” His sister muttered, her eyes leaking sticky looking tears. She wanted to tell him to leave. She wanted to admit everything to him. But looking at him was causing her heart to pound so loudly and roughly against her chest that she couldn’t do anything. All that she could do was watch him, his arms squeezing into her and showering her in his love…

...It wasn’t fair. She didn’t want it to be like this. Why did that Toad have to do this to her..? She just wanted to live at home in peace with her brother. Those feelings inside her heart, about how adorable and how capable he was, were catching fire. Her affection and care for her younger brother was turning against her…

“Anko-oneechan. I’ll get you back to our home. Just sit still.” Tohru said, smiling still as he tried to pull her out of the mud, using every little inch of strength that a boy like him could muster. But to absolutely no avail, the girl having sunk too far into it to be freed with just a mere human’s strength…

His sister took a few deep breaths. The heat inside her. It was growing. Burning away the saliva and mucus that the Toad had forced her to swallow, when it realized that she wanted the same thing it did. To mate with an appropriate male. All it had to do was give her a little push, and then…

“Tohru… Tohru..!” Anko cried out, her irises widening as her eyes turned a deep orange. All while she practically leapt out of the mud that kept her pinned, utilizing the inhuman strength in her legs.

Her brother let out a surprised gasp as he was forced onto the ground by the sudden movement, this time causing him to sink into the sticky mud. “A-Anko-oneechan..?” He felt his heart sinking as he looked up at her, especially at those legs of hers…

They were green and slimy. Just like the mucus that had been covering her. If he were to touch them, they felt just as squishy as the Monsters that had been invading the village… T-There was no way…

“Haaaah… Tohruuuu…” Anko muttered, her tongue lulling out of her mouth as it slowly grew in front of him, reaching all the way down to her chest. The modest chest that was starting to grow, expanding from a mere B cup to a heavy G cup in a matter of seconds. All thanks to the lust she held for the boy underneath her.

Why hadn’t she done this from the beginning? Her heart, pounding against her chest, told her that everything was alright. She had her brother right here, and she had no reason to hold herself back any longer. She could just play with him for ages, and then she’d slather him in mucus, and… and…

Tohru watched in horror as the green from his sister’s thighs spread across her body in a flash, her resistance dying down the longer she spent hovering over him. “A-Anko-oneechan! Please! Resist! Y-You’re not a Monster! You’re my sister!” He cried out, hoping that she wouldn’t turn out the same as all the others had.

His prayers fell on deaf ears as she licked her lips, slathering them in that thick mucus-like saliva. “You’re so cute, Tohru… Ah…” Anko giggled, rubbing her thighs as her ring and little fingers merged together, webbing connecting the rest of them as her toes met a similar fate. There was no way back for her, not any more. Not with her prey right underneath her.

She didn’t hesitate. Not any longer. She used that tongue of hers to rip his clothes off his body, exposing the youth’s adorable frame to the world while also covering it in her mucus and preparing him for what came next. 

Tohru’s cheeks flushed bright red as the mucus absorbed itself into his skin, driving his arousal into the roof. “A-Anko-oneechan…” He muttered, his eyesight turning blurry as his cock grew hard, the thing growing a little as well. He didn’t know what to think. What to do. All that he knew was that he was horny, and that the one above him was his precious onee-chan…

Anko giggled. His thing was so manly now. It was perfect for a Monster like her. In fact, she could feel her lower mouth drooling like mad, wanting to feed on his energy and take in as much of his sperm as she possibly could…

The transformed girl, now a Mucus Toad like the one that had attacked her, squatted down until she felt her hips brushing up against his and the boy’s cock sinking its way into her folds in the process. 

Once they were connected, her newfound instincts took over. And thus she jumped. Using those powerful legs to leap up. Which didn’t accomplish much in terms of actual height, but it let her do the ‘thrusting’ for her dear brother. Letting him sink as deep into her as he possibly could, all while still stuck in the mud underneath.

With every leap she made, her ass grew. Tohru could feel it, as it slammed harder and harder down on him with every passing moment. Not that he focused on that feeling, as his poor eyes were transfixed on her face and her breasts…

Those massive melons kept him lulled into a sedated state. Watching them jump up and down with his sister’s corrupted body. It kept him from struggling. Not that he had a chance to do that any longer. With her weighing down on him, and with his body still stuck within the mud… He couldn’t do anything except for watch like the good little brother that he was.

Eventually, a scream left his lips. Just for a moment, before his sister shot her tongue into his mouth, locking them in a kiss. Letting their climactic roars echo out inside one another, while she absolutely smothered his poor throat in her arousal-inducing mucus…

His hips pumped forward just once, before the juices within his balls fired out. Leaving him quickly drained, as his youthful thing was never designed to cum this early. And yet, his rod remained hard, thanks to the mucus within him.

Anko didn’t break her kiss. Nor did she stop jumping. She was still hungry. She wanted much, much more… And more importantly than that…

She wanted her beloved Tohru to love her just as much as she did. The thought that had condemned them both to this fate, for the rest of their lives.

Thus, the Mucus Toad continued to bounce. Milking away at her brother, who slowly began to change to fit her needs as well...


End file.
